Re: Alex's gibbon-like CA

Alex Duncan (aduncan@mail.utexas.edu)
9 Nov 1995 14:37:21 GMT

In article <815876603snz@crowleyp.demon.co.uk> Paul Crowley,
Paul@crowleyp.demon.co.uk writes:

>Pull the other one, Alex. You boobed. If you had meant "isolation"
>you would have said "isolation". I go on about my "cute little
>'evolution forces' idea" because it's an appalling error, it's
>appallingly common, and people who should know better (like your
>own good self) make it all the time.

I suggest, and you may be believe me if you wish (I don't care), that the
idea of geographic isolation of small subpopulations is almost implicit
in any discussion of speciation events. I didn't bother to spell it out,
and didn't feel I should have to. I took it as a given that you would
know that geographic isolation is implicit in such a discussion, and
would credit me for knowing so as well. I see I made an error. If you
feel it's necessary to have a stereotypical physical anthropologist in
your head, and to lump me in that category -- fine.

As far as the "evolution forces" thing goes -- it is a common assumption
in the evolutionary sciences that changing environments may result in new
adaptations (and thus, speciation). This is not supposed by anyone to
THE cause of evolutionary change. Nonetheless, when large-scale climatic
changes happen to coincide with numerous speciation events (as has been
demonstrated for the African Neogene), it is tempting to speculate that
significant evolutionary change and change in habitat are somehow
correlated.

Alex Duncan
Dept. of Anthropology
University of Texas at Austin
Austin, TX 78712-1086
512-471-4206
aduncan@mail.utexas.edu